1. Field of the Invention
The present invention relates to a parallel logging method for a transaction processing system, and more particularly, to a parallel logging method for a transaction processing system that can simultaneously execute a parallel write of logs (i.e., status information) of application transactions using a plurality of log managers.
2. Background of the Related Art
The transaction log for writing status information of transactions executes writing of the transaction status information for transaction recovery in a storage device such as a disc. The input/output (I/O) work for storing such transaction status information requires a lot of time in comparison to an operational work of a computer processor, and this causes the whole performance of the transaction processing system to deteriorate. Also, in case of using one transaction log storage device, only a serial writing of logs is possible, and thus the whole performance of the transaction processing system is in dependence on the transaction log.
The existing transaction process including the above feature has been changed from a centralized type around a database server to a distributed processing type, i.e., client-server type. Recently, the transaction processing applications mainly follow a client-server model for the distributed transaction process. To support the above-described client-server model and to improve the performance of the transaction processing, a transaction processing monitor has been introduced and applied to general works.
The transaction processing monitor is a kind of system software for solving the problems such as a system down that may be produced due to a computer environment having a different operating system, a compatibility obstacle of application software, etc., under the client-server environment. The transaction processing monitor is well known as middleware.
Also, the conventional transaction processing system has its own single log storage device depending on the transaction processing system. This causes a bottleneck phenomenon during the writing of logs since the status information of the transactions are sequentially written in the single log storage device one by one during the transaction commit process.
As a prior art transaction processing system having the above-described feature, there is a Korean Patent No. 10-092811-0000 xe2x80x9cLog/recovery management method for a transaction processing systemxe2x80x9d issued to Electronics and Telecommunications Research Institute in 1995. According to this prior art technique, the consistency of transaction data is guaranteed in a manner that a before image of a data block to be updated in the transaction is written in a log file, and the corresponding data block is recovered by the image before update when the transaction processing is canceled midway. However, the prior art transaction processing system has the disadvantages in that since it writes in serial the image before update of the data updated in the transaction in one log file, a bottleneck phenomenon may occur due to the writing that is executed using the before image.
Also, in case of the transaction processing system including the above-described feature, the before image of the data being updated is written in the log (i.e., file or disc) in order to guarantee the consistency of the transaction data as in the existing database management system. However, in case of the high-performance transaction processing system for processing the transactions using the transaction processing monitor, the corresponding transaction data is not directly managed as the data in the database, but only the status information of the transactions is written in the log by the transaction processing monitor to guarantee the consistency of the data when the data stored in various kinds of databases such as Informix, Oracle, etc., are updated in one transaction.
Accordingly, the present invention is directed to a parallel logging method for a transaction processing system that substantially obviates one or more problems due to limitations and disadvantages of the related art.
It is an object of the present invention to provide a parallel logging method for a transaction processing system that can prevent the bottleneck phenomenon occurring in plural log storage sections, and improve the performance of the whole system by reducing the time for writing the status of plural transactions. To achieve the object, plural log managers, which execute the corresponding log write in accordance with a log write request message received from a log queue manager, simultaneously execute the corresponding log write in parallel through the plural log storage sections.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided a parallel logging method for a transaction processing system for processing transactions of application programs, the method comprising a first step of a transaction control section instructing transaction participants to execute a transaction preparing step and a transaction commit step in accordance with transaction end requests of the application programs that have executed transaction operations; a second step of a log queue manager receiving a log write request for status information of the transactions requested from the transaction control sections; and a third step of simultaneously executing the log write of the corresponding transactions in parallel through a plurality of log managers in accordance with a request of the log queue manager that has received the log write request.
In another aspect of the present invention, there is provided a transaction processing system for processing transactions of application programs, comprising a transaction manager for generating and managing a plurality of transactions in accordance with transaction processing requests of the application programs, a transaction control section for instructing transaction participants to execute transaction preparing and transaction commit steps requested from the transaction manager, a log queue manager for receiving and managing a log write request of status information of the transactions requested from the transaction control section, and a plurality of log managers for simultaneously executing the log write in parallel and providing resultant values of the parallel log write to the log queue manager in accordance with a log write request message transmitted from the log queue manager.
In still another aspect of the present invention, there is provided a recording medium for storing a program that is readable and executable by a computer and that can perform a parallel logging method for a transaction processing system for processing transactions of application programs, wherein a transaction control section instructs transaction participants to execute a transaction preparing step and a transaction commit step in accordance with transaction end requests of the application programs that have executed transaction operations, a log queue manager receives a log write request for status information of the transactions requested from the transaction control sections, and a plurality of log managers simultaneously execute a log write of the corresponding transactions in parallel in accordance with a request of the log queue manager that has received the log write request.
The transaction can give solutions to the conditions that may be produced due to unexpected problems (caused by a temperature, electromagnetic wave, humidity, overcurrent, unstable power supply, bad contact state of cables, and various kinds of complex causes) by integrally executing various kinds of related works. The transaction guarantees the data integrity, and improves the high-speed concurrency of the corresponding processed data.
That is, the transaction is a unit of work that guarantees the consistency of the transaction data by completely executing and terminating a work composed of various operations or by returning to its initial state before the work is executed.
Also, the transaction is executed through on-line in the same manner as a data transmission/reception through a communication line linked between a terminal device and a computer system, message exchange, inquiry-reply processing, etc., and is applied to a home shopping and a home banking that process a reserved order by a transaction service that is the representative service of an order entry as well as to a reserved order processing for hotels, theaters, trains, airplanes, etc.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.